ALAM SEMESTA YANG HILANG

Para ahli astronomi telah mengetahui bahwa objek di alam semesta ini jauh lebih banyak daripada yang bisa kita lihat secara langsung. Itu mirip gunung es. Bagian gunung es yang kita lihat mengapung di atas permukaan air hanya sepersepuluh dari keseluruhan bongkahan gunung es. Sembilan persepuluh sisanya tersembunyi di bawah air, tak tampak.

Di alam semesta kita, gas, bintang-bintang, dan galaksi-galaksi yang bisa kita lihat hanyalah sekitar 4 persen dari keseluruhan objek yang ada. Kita bisa mengetahui ada yang tidak bisa kita lihat karena "sesuatu" yang tak tampak itu mengerahkan gaya gravitasi. Gravitasi itu menarik objek yang bisa kita lihat. Namun, gravitasi-lah satu-satunya petunjuk yang kita punyai. Objek tak tampak itu tidak memancarkan radiasi yang bisa kita deteksi sehingga para ahli astronomi menyebutnya sebagai zat gelap (dark matter).

Tersusun dari apakah zat gelap itu? Kita tidak tahu. Zat gelap bukan sekedar bintang gelap atau planet gelap atau bahkan lubang hitam. Bisa jadi zat gelap itu zarah-zarah sangat kecil yang berjumlah banyak sekali. Kita tahu, apapun wujudnya, 23% alam semesta berupa zat gelap,

ENERGI GELAP

Jadi, jika sekitar 27% alam semesta berupa zat biasa dan zat gelap, 73% sisanya berupa apa? Sesuatu yang lebih misterius lagi, bernama energi gelap. Hingga akhir 1990-an kita bahkan tidak mengenal energi gelap. Kemudian ahli astronomi menemukan bahwa alam semesta tidak hanya mengembang, tapi pengembangannya mengalami percepatan. Penemuan ini mengejutkan mereka.

Kita masih belum mengetahui sumber energi yang menyebabkan percepatan ini. Apakah sejenis medan energi ataukah sifat ruang itu sendiri? Ataukah kita sama sekali keliru dalam hal beberapa fakta dasar terkait fisika dan gravitasi? Apakah energi gelap akan menyebabkan para pakar fisika menulis ulang hukum fisika supaya bisa memahami alam semesta? Satu hal yang betul-betul kita ketahui adalah alam semesta lebih aneh dari yang pernah kita bayangkan.

Zat misterius bernama zat gelap menyelubungi semua galaksi di alam semesta, menjaganya supaya tetap bersatu dan mencegahnya tercerai berai . Kekuatan lai bernama energi gelap melakukan hal yang berlawan berusaha memisahkan segala sesuatu di alam semesta. Gabungan zat gelap dan energi gelap menyusun 96% alam semesta kita. Keduanya tak tampak bagi kita.

SEGALA SESUATU YANG KITA LIHAT ADALAH SEJARAH

Teleskop adalah mesin waktu, tapi mesin waktu yang membawa kalian ke masa lalu saja. Itu karena objek-objek di langit bukan sebagaimana keaadaan sekarang melainkan keadaannya dahulu.

Untuk memahaminya, coba ingat kalau teleskop itu mengumpulkan cahaya dari langit. Cahaya membutuhkan waktu sampai ke kita, bahkan meskipun bergerak dengan kecepatan 186.000 mil (300.000 km) per jam yang disebut kecepatan cahaya. Cahaya dari Matahari mencapai bumi dalam waktu delapan menit, jadi kita melihat matahari dalam kondisi delapan menit yang lalu.Cahaya dari pluto membutuhkan waktu empat jam untuk sampai ke kita karena harus menempuh jarak 3 milyar mil (5 milyar km)/

JARAK JAUH

Begitulah kalian bergerak keluar tata surya, jarak menjadi bukan main besarnya. Dalam setahun Bumi, cahaya menempuh jarak enam trilyun mil. Bintang terdekat dengan Matahari, Alpha Centauri, berjarak 24 trilyun mil (41 trilyun km). Pusat Bimasakti berjarak 125 ribu trilyun mil.

Angka-angka jarak menjadi sangat besar sehingga para ahli astronomi menciptakan istilah untuk menjelaskan jarak di jagat raya: tahun cahaya. Satu tahun cahaya adalah jarak yang ditempuh cahaya dalam waktu satu tahun Bumi, jadi satu tahun cahaya sama dengan enam trilyun mil (10 trilyun km). Karena cahaya dari Alpha Centauri membutuhkan waktu empat tahun hingga sampai ke kita, kita mengatakan Alpha Centauri berada pada jarak 4 tahun cahaya.

WAKTU LIHAT - KEMBALI

Waktu lihat-kembali (look-back time) adalah seberapa jauh kita kembali ke masa lalu ketika melihat objek di langit. Waktu lihat-kembali Alpha Centauri adalah 4 tahun. Bintang merah Aldebaran di rasi Taurus sekitar 65 tahun cahaya jauhnya, jadi bintang ini punya waktu lihat-kembali 65 tahun. Ketika menatap Aldebaran, kita melihat bintang itu sebagaimana keadaannya 65 tahun lalu. Itu seperti melihat foto kakek-nenek kalian ketika mereka masih anak-anak. Waktu tempuh cahaya menjadi semakin lama ketika kalian menatap keluar Galaksi Bimasakti. Sebagai contoh , galaksi terdekat dengan kita adalah galaksi spiral Andromeda, yang jauhnya 2,5 juta tahun cahaya. Cahaya yang kita lihat dari galaksi Andromeda meninggalkan galaksi tersebut ketika nenek moyang pertama manusia muncul di bumi lebih daripada 3 juta tahun lalu.

Teleskop bagaikan mesin waktu karena kita bisa melihat objek-objek sebagaimana keadaannya pada masa lalu. Cahaya dari Matahari membutuhkan waktu 8 menit 20 detik untuk sampai di Bumi, jadi kita melihat Matahari sebagaimana keadaannya 8,3 menit yang lalu.

SIKLUS HIDUP BINTANG

Para penyair boleh mengatakan bintang hidup selamanya, tapi para ilmuwan tahu itu tidak benar. Semua bintang pada akhirnya akan mati kalau bahan bakar nya habis.

Kalian mungkin mengira kalau bintang yang lebih besar akan hidup lebih lama karena punya lebih banyak bahan bakar. Tapi, makin cepat bintang membakar bahan bakarnya, dan makin pendek masa hidupnya. Bintang paling masif akan hidup beberapa juta tahun saja, sedangkan yang paling tidak masif bisa hidup selama trilyunan tahun.

Semua bintang menghabiskan sebagian besar hidupnya  untuk menggabungkan hidrogen dan mengubahnya menjadi helium di intinya. Fusi nuklir ini menciptakan energi yang kita lihat sebagai cahaya bintang. Akhirnya inti bintang pun kehabisan hidrogen. Seperti itulah akhir hidup bintang bermassa rendah seperti Matahari kita.

Ketika bintang bermassa lebih tinggi kehabisan hidrogen, bintang tersebut bisa mulai membakar helium di inti dan menghasilkan karbon dan oksigen. Bintang yang paling masif bisa membakar unsur yang lebih berat dan lebih berat lagi hingga intinya penuh dengan besi yang sangat rapat dan panas. Itulah akhir perjalanan hidup bintang tersebut, karena tidak ada energi yang dihasilkan dari reaksi fusi besi.

Semua bintang berasal dari nebula (ilustrasi kiri atas), tapi masing-masing menempuh jalan hidup yang berlainan. Bintang-bintang yang lebih kecil (baris atas) berakhir sebagai katai putih yang mungil. Namun, bintang yang lebih masif (baris bawah) meledak sebagai supernova, meninggalkan lubang hitam atau bintang neutron

International Space Station Enables Interplanetary Space Exploration

Technology demonstrations aboard the International Space Station help drive space exploration.

Image Credit: 

NASA

The first 3-D printer ever tested in orbit, now operating aboard the International Space Station, may help to manufacture parts quickly and cheaply in space.

Image Credit: 

NASA

If necessity is the mother of invention, then survival in space breeds many “children.” These children are the research and technologies demonstrated aboard the International Space Station. For 16 years, the station has provided researchers a platform in microgravity where they perform experiments and test technologies to allow humans to travel farther into the solar system than ever before. From life support systems to growing plants in space, the space station continues to drive human exploration for missions beyond low-Earth orbit.

NASA’s Orion spacecraft, which is set to blast off on its first flight test in December, will demonstrate many technologies first tested aboard the space station. Orion, built to transport humans into deep space, embarks on a two-orbit, four-hour "Trial By Fire" on Dec. 5 to test many of its critical systems.

"Without what we’ve learned from having a continuous human presence in space for more than a decade, we wouldn’t be able to think about sending people into deep space onboard Orion,” said Mark Geyer, Orion Program manager. “We’re testing out technologies and concepts on the space station right now that are necessary for the kind of long-duration trips Orion enables.”

Technology demonstrations aboard the station beget new systems and concepts for on Earth and for space exploration. For example, the amine swingbed, which uses organic compounds with modified ammonia atoms, controls carbon dioxide and humidity in Orion. This type of recovery system also can operate on Earth to help remove carbon dioxide and humidity in tight spaces, like in mine tunnels or submarines.

With successful demonstrations of 3-D printing on the space station, the potential now exists to manufacture parts quickly and cheaply in space. Instead of waiting for a cargo delivery, astronauts could replace filters or faulty equipment simply by printing new parts. Researchers are gaining insight into improving 3-D printing technology on Earth by testing it in microgravity. This knowledge could help advance industry printing methods.

Environmental control and life support systems (ECLSS) aboard the station support humans in space. ECLSS includes wastewater recycling to provide clean water for bathing and drinking. It also includes oxygen generation systems to provide air for crews to breathe. These and other components of ECLSS help cut transportation costs for resupply and provide astronauts a habitable environment. This technology demonstration helps engineers design and develop improved closed-loop life support systems for long duration spacecraft.

"Testing various life support sub-systems is an ideal use of the space station," said George Nelson, manager of NASA’s International Space Station Technology Demonstration. "Reliability of these systems on long duration missions is paramount. We can verify design reliability in the microgravity environment by using them on the station without any mission or crew risk, since the existing space station systems are always available."

Human behavioral health and performance also is taken into account for deep space missions where crew members reside in confined spaces for long periods of time. One study evaluates the effects of delayed communications for interplanetary crews that have to handle medical and other emergencies. This type of research also may help refine procedures for Earth-based teams that operate in extreme or remote environments with limited contact with a home base and its experts. Additionally, NASA recently announced funding for three proposals to help answer questions about neurological conditions related to behavioral health and performance on deep space exploration missions.

Finally, plant growth facilities on the station like Veggie may one day produce safe, fresh and nutritious crops for astronauts while giving the crew opportunities for relaxation and recreation. Using these facilities, researchers can glean knowledge about plant growth and development in microgravity. This information may improve growth, biomass production and farming practices on Earth.

Necessities for survival in space breed innovations aboard the space station. Like a mother to her child, these inventions areimproving life on Earth and, one day, may support humans on the planets beyond. 

Jay Perry, Environmental Control and Life Support Systems engineer, discusses how systems aboard the International Space Station provide and recycle air and water to eliminate the need for resupply on cargo spacecraft.

Laura Niles
International Space Station Program Science Office and Public Affairs Office
NASA’s Johnson Space Center

( http://www.nasa.gov/mission_pages/station/research/news/orion_tests_technology/index.html#.VIV6WDGG9uA )

Exploring Comets and Asteroids is an International Endeavor

NASA and space agencies across the globe are opening up new possibilities for space exploration with missions to comets, asteroids, and other celestial bodies.

Following NASA, European Space Agency (ESA), and Indian Space Research Organisation (ISRO) spacecraft observations of the close flyby of Mars by comet Siding Spring in October, and the successful November landing of ESA’s Philae lander on comet 67P/Churyumov–Gerasimenko, the Japan Aerospace Exploration Agency (JAXA) successfully launched its Hayabusa2 mission on Dec. 3 to rendezvous with an asteroid, land a small probe plus three mini rovers on its surface, and then return samples to Earth.

Asteroid Explorer “Hayabusa2” is a successor of “Hayabusa” (MUSES-C), which revealed several new technologies and returned to Earth in June 2010.

Image Credit: 

JAXA and Akihiro Ikeshita

NASA and JAXA are cooperating on the science of the mission and NASA will receive a portion of the Hayabusa2 sample in exchange for providing Deep Space Network communications and navigation support for the mission.

Hayabusa2 builds on lessons learned from JAXA’s initial Hayabusa mission, which collected samples from a small asteroid named Itokawa and returned them to Earth in June 2010. Hayabusa2’s target is a 750 meter- wide asteroid named 1999 JU3, because of the year when it was discovered by the NASA-sponsored Lincoln Near-Earth Asteroid Research project, Lexington, Massachusetts. This is a C-type asteroid which are thought to contain more organic material than other asteroids. Scientists hope to better understand how the solar system evolved by studying samples from these asteroids.

“We think of C-type asteroids as being less altered than others,” says Lucy McFadden, a planetary scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Bringing that material back and being able to look at it in the lab — I think it’s going to be very exciting.”

On Nov. 17, NASA and JAXA signed a Memorandum of Understanding for cooperation on the Hayabusa2 mission and NASA’s Origins, Spectral Interpretation, Resource Identification, Security – Regolith Explorer (OSIRIS-REx) mission to mutually maximize their missions’ results. OSIRIS-REx is scheduled to launch in 2016. It will be the first U.S. asteroid sample return mission. OSIRIS-REx will rendezvous with the 500-meter-sized asteroid Bennu in 2019 for detailed reconnaissance and a return of samples to Earth in 2023.

Hayabusa2 and OSIRIS-REx will further strengthen the two space agencies’ relationship in asteroid exploration.

The missions will also help NASA choose its target for the first-ever mission to capture and redirect an asteroid. NASA's Asteroid Redirect Mission (ARM) in the 2020s will help NASA test new technologies needed for future human missions for the Journey to Mars.

Comets and asteroids contain material that formed in a disk surrounding our infant sun. The hundreds of thousands of known asteroids are leftovers from material that didn't coalesce into a planet or moon in the inner solar system. The thousands of known comets likely formed in the outer solar system, far from the sun's heat, where water exists as ice.

Larger objects, like dwarf planets Pluto and Ceres, also formed in the outer solar system, where water ice is stable. Pluto and Ceres will soon be explored by NASA missions New Horizons and Dawn, respectively. Asteroids and comets are of unique interest to scientists, though, because they could hold clues to the origins of life on Earth.

These missions have greatly increased scientific knowledge on Earth about our solar system and the history of our planet. Many scientists suspect we could find organic material in asteroids and comets, like amino acids—critical building blocks for life, which could help answer questions about the origins of life on Earth. These questions drive us to continue exploring the intriguing asteroids and comets of our solar system.

Multiple missions that are operating in space or in development by NASA and international partners could bring us much closer to answering that question in our lifetimes and also help identify Near-Earth Objects that might pose a risk of Earth impact, and further help inform developing options for planetary defense. 

Follow the latest missions and discoveries at:

http://www.nasa.gov/asteroid-and-comet-watch/

( http://www.nasa.gov/content/exploring-comets-and-asteroids-is-an-international-endeavor/index.html#.VIV5ODGG9uA )

Hagupit (Northwestern Pacific Ocean)

This TRMM satellite image of Super Typhoon Hagupit on December 4, 2014 at 1721Z showed that the heaviest rainfall was just southwest of a well-defined eye.

Image Credit: 

NASA/JAXA/SSAI, Hal Pierce

Station-RapidScat instrument captured data on Hagupit's winds. The RapidScat image showed sustained winds of at least 30 meters per second (red) around the eye of the storm.

Image Credit: 

 NASA JPL

NASA-NOAA's Suomi NPP satellite flew over Super Typhoon Hagupit on Dec. 5 at 4:22 UTC (Dec. 4 at 11:22 p.m. EDT) and the VIIRS instrument showed the 12 mile-wide eye.

Image Credit: 

NASA/NOAA

NASA Analyzes Super Typhoon Hagupit's Rains and Wind on Philippine Approach

Super Typhoon Hagupit is forecast to make landfall in the eastern Philippines bringing heavy rainfall, damaging winds and storm surge. NASA/JAXA's TRMM satellite and the RapidScat instrument provided rainfall and wind data, while NASA-NOAA's Suomi NPP satellite provided a visible image of the storm. In the Philippines, Hagupit is known locally as "Typhoon Ruby."

The Tropical Rainfall Measuring Mission or TRMM satellite caught a good view of Super Typhoon Hagupit on December 4, 2014 at 1721 UTC (12:21 p.m. EST) when its sustained winds were estimated at over 145 knots (166.8 mph). TRMM's Microwave Imager (TMI) showed that the heaviest rainfall was just southwest of a well-defined eye. 

About three hours later the International Space Station-RapidScat instrument captured data on Hagupit's winds. The RapidScat image showed sustained winds of at least 30 meters per second (67 mph/108 kph) around the eye of the storm.

NASA-NOAA's Suomi NPP satellite flew over Super Typhoon Hagupit on Dec. 5 at 4:22 UTC (Dec. 4 at 11:22 p.m. EDT) and the Visible Infrared Imaging Radiometer Suite or VIIRS instrument aboard captured a visible image of the storm. The VIIRS image showed a symmetric ring of intense thunderstorms surrounding the 12-nautical-mile-wide eye.

VIIRS is a scanning radiometer that collects visible and infrared imagery and "radiometric" measurements. Basically it means that VIIRS data is used to measure cloud and aerosol properties, ocean color, sea and land surface temperature, ice motion and temperature, fires, and Earth's albedo (reflected light).

At 1500 UTC (10 a.m. EST) on Dec. 5, Super Typhoon Hagupit's maximum sustained winds were near 130 knots (149.6 mph/241 kph), down from 150 knots (172 mph/277.8 kph). Typhoon-force winds extend out 40 nautical miles (46 miles/74 km) from the center, while tropical-storm-force winds extend out to 120 miles (138 miles/222 km).

Hagupit was centered near 12.1 north longitude and 128.2 east latitude, about 465 nautical miles (535 miles/861 km) southeast of Manila, Philippines. Hagupit continued moving in a west-northwesterly direction. The storm is generating very rough and dangerous seas with wave heights to 45 feet (13.7 meter).

According to the Joint Typhoon Warning Center (JTWC) forecast, Super Typhoon Hagupit will "maintain intensity until it starts interacting with land near 24 hours (1500 UTC/10 a.m. EST on Dec. 6) then the system will begin rapidly weakening."

Many warnings are in effect throughout the Philippines. Public storm warning signal #2 is in effect in the following provinces: Visayas: Northern and eastern Samar, Samar, Biliran, Leyte, southern Leyte, northern Cebu and Cebu City, Bantayan Island and Camotes Island. In Luzon, signal #2 is in effect for: Albay, Sorsogon, Ticao Island and Masbate.

Public storm warning signal #1 is in effect in the Province of Visayas including: Capiz, Iloilo, Antique, Guimaras, Aklan, Negros Oriental & Occidental, rest of Cebu, Siquijor and Bohol. Signal #1 is also in effect in the Mindanao Province for Surigao del Sur, & Norte, Misamis Oriental, Agusan del Sur & Norte, Dinagat Island and Camiguin Island; and in the Province of Luzon, including: Catanduanes, Camarines Norte & Sur, Burias Island and Romblon.

On Dec. 5 at 10 a.m. EST (1500 UTC) the latest update from the Philippine Atmospheric, Geophysical and Astronomical Services Administration known as PAGASA called for expected landfall on Saturday evening (Dec. 6) or Sunday morning (Dec. 7) over the Eastern Samar – Northern Samar area and it will be associated with strong winds, storm surge (up to 4 meters) and heavy-intense rainfall.

PAGASA noted:

• "Estimated rainfall amount is from 7.5 – 20 mm per hour (heavy – intense) within the 600 km diameter of the typhoon.

• Ruby (Hagupit) and the Northeast Monsoon will bring rough to very rough sea conditions over the seaboards of Northern Luzon, eastern seaboard of Central and Southern Luzon, seaboards of Visayas and over northern and eastern seaboards of Mindanao. Fishermen and those using small seacraft are advised not to venture out over the said seaboards."

For more information and updates visit: www.pagasa.dost.gov.ph or http://meteopilipinas.gov.ph/map.php.

Hagupit is tracking generally westward along the southwestern edge of a subtropical ridge (elongated area) of high pressure which is located south of Japan. Over the next three days, Hagupit is forecast to track west to west-northwest under the influence of that area of high pressure.     

Rob Gutro
NASA's Goddard Space Flight Center

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Dec. 04, 2014 - NASA Observes Super Typhoon Hagupit; Philippines Under Warnings

On Dec. 4 at 02:10 UTC, the MODIS instrument aboard NASA's Terra satellite took this visible image of Super Typhoon Hagupit approaching the Philippines.

Image Credit: 

NASA Goddard's MODIS Rapid Response Team

The TRMM satellite traveled directly over Typhoon Hagupit's eye on December 3, 2014 at 0342 UTC and the heaviest rainfall appears in red.

Image Credit: 

NASA/SSAI/JAXA, Hal Pierce

The GPM core satellite had a good view of Hagupit at 1041 UTC on Dec. 3 and showed that rain was falling at a rate of over 138 mm (~5.4 inches) per hour in the western side of Hagupit's eye.

Image Credit: 

NASA/SSAI/JAXA, Hal Pierce

This RapidScat windmap of Hagupit shows the position of storm on Dec. 2 (right) and Dec. 3 (center). The storm moved a few hundred miles between these times. Winds in red were over 30 meters per second (108 kph/67 mph).

Image Credit: 

NASA JPL

Forecasters at the Joint Typhoon Warning Center expect Super Typhoon Hagupit to reach peak intensity today, Dec. 4, and although expected to weaken, will remain a Category 4 typhoon when it approaches the east central Philippines. NASA's Terra satellite and NASA/JAXA's GPM and TRMM satellites have been providing forecasters with valuable data on the storm. Computer models have varied on their track for the storm based on the strength of an upper-level system, so satellite data is extremely valuable in helping determine where Hagupit will move.

On Dec. 3, typhoon Hagupit was moving from near Palau toward the Philippines when it was examined by two satellites managed by NASA and the Japan Aerospace Exploration Agency known as JAXA. The Tropical Rainfall Measuring Mission or TRMM satellite and the Global Precipitation Measurement or GPM core satellite passed over Hagupit and gathered rainfall and cloud height data.

The TRMM satellite traveled directly over Typhoon Hagupit's eye on December 3, 2014 at 0342 UTC (Dec. 2 at 10:42 p.m. EST). The GPM (core satellite) had a good view of Hagupit later at 1041 UTC (5:41 a.m. EST) Rainfall data captured at that time with GPM's Microwave Imager (GMI) instrument shows that rain was falling at a rate of over 138 mm (~5.4 inches) per hour in the western side of Hagupit's eye.

At NASA's Goddard Space Flight Center in Greenbelt, Maryland the data from the Ku band on GPM's dual frequency radar instrument (DPR) was used to create a 3-D image. The Ku band radar swath showed powerful thunderstorms reaching heights of over 15.8 km (9.8 miles) in feeder bands west of Typhoon Hagupit's eye.

On Dec. 4 at 02:10 UTC, the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument aboard NASA's Terra satellite took a visible image of Super Typhoon Hagupit approaching the Philippines. The MODIS image showed a clear eye surrounded by strong thunderstorms and bands of thunderstorms wrapping into the low-level center. The image also showed that the bulk of strongest thunderstorms were being pushed slightly west of the center as a result of easterly wind shear.

At 1500 UTC (10 a.m. EST) Typhoon Hagupit's maximum sustained winds were near 150 knots (172.6 mph/ 277.8 kph). Currently, typhoon-force winds of 64 knots (74 mph/118.5 kph) or higher occur out to 55 miles of the center.  Tropical Storm-force winds of 34 knots (39 mph/63 kph) or higher occur within 85 to 140 miles of the center. The eye was centered near 11.1 north longitude and 130.9 east latitude, about 640 nautical miles (736 miles/1,185 km) east-southeast of Manila, Philippines. Hagupit was moving to the west-northwest at 12 knots 13.8 mph/22.2 kph).

Warnings in Effect

Philippines warnings in effect as of Dec. 4 include: Public storm warning signal #2 for the following provinces: Visayas: Northern and eastern Samar, Samar, Biliran, Leyte and southern Leyte

Mindanao: Dinagat Island and Siargao Island. And public storm warning signal #1 in effect for the following provinces: Visayas: Northern Cebu including Bantayan island, Camotes island and Bohol; Mindanao: Surigao del Norte & Sur, Camiguin Island and Agusan del Norte; Luzon: Catanduanes, Albay, Sorsogon, Ticao Island and Masbate.

Current Forecast Track from the JTWC

The Joint Typhoon Warning Center (JTWC) current forecast track for Super Typhoon Hagupit projects the eye of the typhoon just over the northeastern tip of Eastern Visayas on Dec. 6 before making landfall over the Bicol region on Dec. 7. The storm is forecast to continue tracking in a northwesterly direction thereafter.

Maximum sustained winds at the time of approach to Eastern Visayas are expected be at Category 4 strength on the Saffir-Simpson scale, although the interaction with land is expected to continue weakening the storm.  

The JTWC forecast calls for Hagupit to remain at typhoon strength as it crosses the Philippines and moves into the South China Sea.

Question in the Forecast Track

As of Dec. 4, not all computer models agree on the exact track the storm will take because of an area of low pressure forecast to move in from the north. Some computer models project that the low pressure system will be strong and would take Hagupit on a more westerly direction over the Central Philippines. Other computer models are projecting that the low pressure area to the north of Hagupit will not be so strong, which will allow the storm to maintain movement in a northwesterly direction.

As satellites gather more information, computer models will update atmospheric conditions that will steer the storm and forecasters will reassess the track as Hagupit nears the Philippines over the next couple of days.

Rob Gutro
NASA's Goddard Space Flight Center, Greenbelt, Maryland

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Dec. 3, 2014 - NASA Tracks Intensifying Typhoon Hagupit

NASA's Aqua satellite captured this image of Typhoon Hagupit on Dec. 3 at 04:30 UTC in the western Pacific Ocean.

Image Credit: 

NASA Goddard MODIS Rapid Response

This image from the Rapidscat instrument aboard the ISS was taken when Hagupit was a tropical storm on Dec 2 at 8:50 a.m. GMT and had 25 meters/second winds (50 knots/57.5 mph/92.6 kph).

Image Credit: 

 NASA JPL

Typhoon Hagupit continues to intensify as it continued moving through Micronesia on Dec. 3 triggering warnings. NASA's Aqua satellite passed overhead and captured an image of the strengthening storm while the Rapidscat instrument aboard the International Space Station provided information about the storm's winds.

The International Space Station-RapidScat instrument monitors ocean winds to provide essential measurements used in weather predictions, including hurricanes. "RapidScat measures wind speed and direction over the ocean surface and captured an image of Hagupit when it was a tropical storm on Dec 2 at 8:50 a.m. GMT," said Doug Tyler of NASA's Jet Propulsion Laboratory, Pasadena, California. "The growing storm, north of New Guinea and headed for the Philippines, already had 25 meters/second winds (50 knots/57.5 mph/92.6 kph)."

A typhoon and tropical storm warning are in effect in Micronesia, in addition to a typhoon watch as Hagupit marches through Micronesia on a west-northwesterly track. A typhoon warning is in effect for Yap and Ngulu in Yap state, and a typhoon watch and tropical storm warning is in effect for Kayangel in the Republic of Palau. In addition, a tropical storm warning is in effect for Koror in the Republic of Palau.

NASA's Aqua satellite captured a visible image of Typhoon Hagupit on Dec. 3 at 04:30 UTC (Dec. 2 at 11:30 p.m. EST) as it moved through Micronesia in the western Pacific Ocean. The image showed a concentration of strong thunderstorms around the center with bands of thunderstorms spiraling into it. 

At 1500 UTC (10 a.m. EST) on Dec. 3, Typhoon Hagupit's maximum sustained winds had increased to 100 knots 115.1 mph/185.2 kph). Typhoon-strength winds extend 30 nautical miles (34.5 miles/55.5 km) out from the center, while tropical storm force winds extend up to 120 nautical miles (138 miles/222 km). 

The typhoon was centered near 8.7 north longitude and 138.3 east latitude, just 91 nautical miles (104.7 miles/168.5 km) west-southwest of the island of Yap. The typhoon is kicking up very rough seas with wave heights to 34 feet (10.3 meters). It was moving to the west-northwest at 18 knots (20.7 mph/33.4 kph) and is expected to continue in that general direction.

Forecasters at the Joint Typhoon Warning Center (JTWC) expect that Hagupit will continue to move west-northwest through Micronesia while intensifying to a Category four typhoon on the Saffir-Simpson scale peaking at 130 knots (149.6 mph/240 kph) over the next two days before it starts to weaken. The JTWC forecast calls for the typhoon to turn to the northwest and stay to the east of the Philippines.

For more information about Rapidscat, visit: http://www.jpl.nasa.gov/missions/iss-rapidscat/

Rob Gutro
NASA's Goddard Space Flight Center

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This visible image of Tropical Storm Hagupit was taken on Dec. 2 by the MODIS instrument aboard NASA's Aqua satellite.

Image Credit: 

NASA Goddard MODIS Rapid Response

Dec. 02, 2014 - NASA Sees Typhoon Hagupit as Micronesia Posts Warnings

NASA's Aqua satellite captured a visible picture of Typhoon Hagupit in the western North Pacific Ocean on December 2, when several warnings were in effect for islands in Micronesia.

Micronesia warnings include a Typhoon Warning for Woleai, Yap and Ngulu in Yap state, a Typhoon Watch posted for Faraulep, Fais and Ulithi in Yap state, and a Tropical Storm Warning for Faraulep in Yap state.

When NASA's Aqua satellite passed over Hagupit on Dec. 2 at 03:45 UTC (Dec. 1 at 10:45 p.m. EST) the MODIS instrument took a visible picture of the storm that showed it had become much better organized over the previous day. Powerful, high thunderstorms circled the center while bands of thunderstorms spiral in from the west, south and north.

At 1500 UTC (10 a.m. EST) on Dec. 2, Hagupit had become a Category One typhoon on the Saffir-Simpson wind scale with maximum sustained winds near 70 knots (80.5 mph/129.6 kph). Hagupit was centered near 6.2 north longitude and 142.7 east latitude, about 463 nautical miles (532.8 miles/857.5 km) south of Andersen Air Force Base, Guam. It was moving to the west at 17 knots (19.5 mph/31.8 kph) and generating high seas with waves up to 25 feet (7.6 meters).

Forecasters at the Joint Typhoon Warning Center forecast Hagupit to continue moving west-northwest through Micronesia and to intensify to 130 knots before weakening. The forecast track takes the center of Hagupit between Palau and Yap on Dec. 3 and toward the Philippines thereafter.

Weakening is not expected to begin until Dec. 6 so Hagupit is expected to maintain typhoon status through December 7.

Rob Gutro
NASA's Goddard Space Flight Center

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NASA's Terra satellite captured this visible image of Tropical Storm Hagupit in the western Pacific Ocean on Dec. 1 at 00:05 UTC (7:05 p.m. EST, Nov. 30).

Image Credit: 

NASA Goddard MODIS Rapid Response

NASA's Aqua satellite captured infrared data on the Hagupit on Nov. 30 at 9:59 p.m. EST that showed strong thunderstorms with cloud top temperatures exceeding -63F/-53C (purple) around the center.

Image Credit: 

NASA JPL, Ed Olsen

Dec. 01, 2014 -NASA's Terra Satellite Catches Fast-Developing Tropical Storm Hagupit

Tropical Storm Hagupit was just a low pressure area on Nov. 30, but warm waters and good atmospheric conditions allowed the storm to develop rapidly. By Dec. 1 the low pressure area strengthened into a tropical storm when NASA's Terra satellite passed overhead.

The Moderate Resolution Imaging Radiometer known as the MODIS instrument that flies aboard NASA's Terra satellite captured a visible image of Tropical Storm Hagupit in the western Pacific Ocean on Dec. 1 at 00:05 UTC (7:05 p.m. EST, Nov. 30). The picture showed a concentration of strong thunderstorms around the center of circulation and fragmented bands of thunderstorms spiraling into the center from the western quadrant.

Hagupit developed from low pressure area System 95W. On Nov. 30, the Joint Typhoon Warning Center (JTWC) was monitoring System 95W when it was a couple of hundred miles south of the island of Chuuk. Chuuk is an island and one of the four states of the Federated States of Micronesia, located in the western North Pacific Ocean.

By Dec. 1 at 0900 UTC (4 a.m. EST), the low pressure area had been designated as a tropical depression and was renamed Tropical Depression 22W. Six hours later, the storm had quickly intensified into Tropical Storm Hagupit as maximum sustained winds strengthened near 40 knots (46 mph/73 kph). At that time Hagupit was centered about 140 nautical miles south-southwest of Chuuk and was moving toward the west-northwest at 15 knots (17.2 mph/27.7 kph). 

The Joint Typhoon Warning Center noted that animated infrared satellite imagery on Dec. 1 confirmed the low-level circulation center was consolidating and fragmented bands of thunderstorms were wrapping into the low-level center. The Atmospheric Infrared Sounder or AIRS instrument aboard NASA's Aqua satellite captured infrared data on the storm on Dec. 1 at 02:59 UTC (Nov. 30 at 9:59 p.m. EST). The AIRS data showed strong thunderstorms with cloud top temperatures exceeding -63F/-53C around the center, which indicated the storms were high in the troposphere and capable of generating heavy rainfall.

The forecast from JTWC calls for slow intensification of the tropical storm over the next day. Thereafter, the storm is expected to intensify rapidly because of improved upper-level atmospheric conditions and warm sea surface temperatures. The JTWC is forecasting Hagupit as a typhoon as its center passes just to the north of the island of Yap on Dec. 3 while continuing to move in a west-northwesterly direction.

There are several warnings and watches now in effect for Tropical Storm Hagupit. A tropical storm warning is in effect for Satawal in Yap state. A typhoon watch is in effect in Faraulep, Woleai, Fais and Ulithi in Yap state, and a  tropical storm watch is in force in Puluwat in Chuuk state.

Rob Gutro
NASA's Goddard Space Flight Center

( http://www.nasa.gov/content/goddard/hagupit-northwestern-pacific-ocean/index.html#.VIV5DDGG9uA )